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Related papers: Calibrating 15 years of GOLF data

200 papers

Disk-integrated observations of the Sun provide a unique vantage point to explore stellar activity and its effect on measured radial velocities. Here, we report a new approach for disk-integrated solar spectroscopy and evaluate its…

We present an analysis of the variability of the solar oscillation spectrum during solar cycle 23 and its extended minimum. We use simultaneous observations of the low-degree solar p modes collected by the space-based, Sun-as-a-star GOLF…

Solar and Stellar Astrophysics · Physics 2010-04-19 D. Salabert , R. A. Garcia , P. L. Palle , S. J. Jimenez-Reyes , A. Jimenez

Gravity modes in the Sun have been long searched during the past decades. Using their asymptotic properties Garcia et al. (2007) found the signature of the dipole g modes analyzing an spectral window between 25 and 140 muHz of velocity…

Astrophysics · Physics 2008-10-10 A. Jimenez , R. A. Garcia

Extreme precision radial velocity (EPRV) measurements contend with internal noise (instrumental systematics) and external noise (intrinsic stellar variability) on the road to 10 cm/s "exo-Earth" sensitivity. Both of these noise sources are…

Solar flares presumably have an impact on the deepest layers of the solar atmosphere and yet the observational evidence for such an impact is scarce. Using ten years of measurements of the Na D$_{1}$ and Na D$_2$ Fraunhofer lines, measured…

Solar and Stellar Astrophysics · Physics 2010-05-21 G. Cessateur , M. Kretzschmar , T. Dudok de Wit , P. Boumier

Quantitative helio- and asteroseismology require very precise measurements of the frequencies, amplitudes, and lifetimes of the global modes of stellar oscillation. It is common knowledge that the precision of these measurements depends on…

Astrophysics · Physics 2009-11-13 Thorsten Stahn , Laurent Gizon

The global rotational profile of the solar atmosphere and its variation at different layers, although crucial for a comprehensive understanding of the dynamics of the solar magnetic field, has been a subject to contradictory results…

We present a photometrically accurate restitution of the K and F coronae from white-light images obtained over 24 Years [1996--2019] by the Large-Angle Spectrometric COronagraph "LASCO-C2" onboard the Solar and Heliospheric Observatory…

Solar and Stellar Astrophysics · Physics 2021-03-31 Antoine Llebaria , Philippe Lamy , Hugo Gilardy , Brice Boclet , Jean Loirat

Recent models of variations of the Sun's structure with the 11-year activity cycle by Sofia et al (2005) predict strong non-homologous changes of the radius of subsurface layers, due to subsurface magnetic fields and field-modulated…

Astrophysics · Physics 2009-11-13 S. Lefebvre , A. G. Kosovichev , J. P. Rozelot

Solar filament oscillations have been known for decades. Now thanks to the new capabilities of the new telescopes, these periodic motions are routinely observed. Oscillations in filaments show key aspects of their structure. A systematic…

Solar and Stellar Astrophysics · Physics 2022-10-26 Manuel Luna , Joan-René Merou Mestre , Frédéric Auchère

Context. Solar-like oscillations exhibit a regular pattern of frequencies. This pattern is dominated by the small and large frequency separations between modes. The accurate determination of these parameters is of great interest, because…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 René Kiefer , Ariane Schad , Wiebke Herzberg , Markus Roth

Context. Aalto University Mets\"ahovi Radio Observatory has collected solar intensity maps for over 45 years. Most data coverage is on the 37 GHz frequency band, tracking emissions primarily at the chromosphere and coronal transition…

Solar and Stellar Astrophysics · Physics 2024-02-21 Sami Kivistö , Frederick Gent , Merja Tornikoski , Joni Tammi , Maarit Korpi-Lagg

One of the largest sources of uncertainty in the computation of globular cluster isochrones and hence in the age determination of globular clusters is the lack of a rigorous description of convection. Therefore, we calibrated the…

Astrophysics · Physics 2009-10-31 Bernd Freytag , Maurizio Salaris

The long-term variations in the orbit of the Earth govern the insolation on its surface and hence its climate. The use of the astronomical signal, whose imprint has been recovered in the geological records, has revolutionized the…

Earth and Planetary Astrophysics · Physics 2023-03-22 Nam H. Hoang , Federico Mogavero , Jacques Laskar

Young and active stars generally have regular, almost sinusoidal, patterns of variability attributed to their rotation, while the majority of older and less active stars, including the Sun, have more complex and non-regular light-curves…

Solar and Stellar Astrophysics · Physics 2020-04-22 E. M. Amazo-Gómez , A. I. Shapiro , S. K. Solanki , N. A. Krivova , G. Kopp , T. Reinhold , M. Oshagh , A. Reiners

Cool main-sequence, sub-giant and red-giant stars all show solar-like oscillations, pulsations that are excited and intrinsically damped by near-surface convection. Many overtones are typically excited to observable amplitudes, giving a…

Solar and Stellar Astrophysics · Physics 2019-04-17 William J. Chaplin , Heather M. Cegla , Christopher A. Watson , Guy R. Davies , Warrick H. Ball

This paper examines long-term temporal and spatial fluctuations in the solar rotation (more than four solar cycles) by investigating radio emission escapes from various layers of the solar atmosphere during the years 1967-2010. The flux…

Solar and Stellar Astrophysics · Physics 2021-07-06 Vivek Kumar Singh , Satish Chandra , Sanish Thomas , Som Kumar Sharma , Hari Om Vats

Radial velocity observations of stars are entering the sub-m/s domain revealing fundamental barriers for Doppler precision experiments. Observations of the Sun as a star can easily overcome the m/s photon limit but face other obstacles. We…

Instrumentation and Methods for Astrophysics · Physics 2016-06-29 Ulrike Lemke , Ansgar Reiners

We show that chirping gravitational waves in the LIGO frequency band $f=1 - 5000$ Hz can be gravitationally diffracted by the Sun, due to the coincidence of its Fresnel length $r_F \propto \sqrt{1\, {\rm AU}/f}$ and the solar radius…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-26 Sunghoon Jung , Sungjung Kim

Context. The contribution of quiet-Sun regions to the solar irradiance variability is currently unclear. Some solar-cycle variations of the quiet-Sun physical structure, such as the temperature gradient, might affect the irradiance. The…

Solar and Stellar Astrophysics · Physics 2018-09-05 M. Faurobert , M. Carbillet , L. Marquis , A. Chiavassa , G. Ricort